iptables question -underflow points - Linux

This is a discussion on iptables question -underflow points - Linux ; I am analyzing the iptables source code.In the kernel an iptable is
represented with the help of an ipt_table struct :-
struct ipt_table
{
struct list_head list;
/* A unique name... */
char name[IPT_TABLE_MAXNAMELEN];
/* What hooks you will enter ...